温敏型大白菜不育系的小孢子败育特性

The Characteristic of Microspore Development in Temperature-sensitive Male Sterile Line on Chinese Cabbage

两系法杂交制种中,温度敏感型雄性不育大白菜的小孢子在不育期的发育各阶段都可能发生畸形、退化,主要有4种类型:第一,花药发育受阻于孢原细胞的分化,属于无花粉型;第二,存在孢原细胞的分裂活动,但形成畸形角隅,孢原细胞退化解体或增大并聚成空洞的薄壁细胞;第三,四分体时期绒毡层和小孢子都退化,只剩空的花粉囊腔和几块残存物;第四,成熟花粉粒时期,小孢子畸形,药室收缩成镰刀形,畸形花粉粒杂乱地挤满药室。

The microspore will be malformation and retrogress at each stage of development in temperature-sensitive male sterile line on Chinese cabbage when producing seed with two-line method. The four major types of malformation and retrogression were as follow: The first, the anther can't develop even before sporogonium differentiation, which belongs to non-pollen type. The second, sporogonium differentiates into abnormal corners, then disintegrates or increases in cell size and aggregates into parenchyma cells. The third, at the period of tetrad, both tapetum and microspore retrogressed, which result in only empty clinandrium cavity and relic. The fourth, at the period of mature pollen grain, the microspore was malformation, anther locule constricted into falcate, abnormal microspore crowded in the whole anther locule out of order.